Re: Why are empty VARCHAR2S always NULL?

Hi Wolfram,

Not sure I quite agree with that.

A numeric having no value doesn't necessarily mean that it should be represented as a 0. For example 0 degrees centigrade doesn't mean an absence of temperature, a score of 0-0 doesn't mean an absence of a score. A 0 is generally used to represent the occurrence of a value, that value being 0. If a swimmer fails to complete a race because of serve cramps in the left leg (gee that brings back bad memories) then the recorded time shouldn't be 0 (ie. they completed the race in no time), this absence of a value should be recorded as well, NULL I guess. No recorded time.

I understand your requirement to differentiate between an unknown value and the known absence of a value. However, the simple use of a space, although not strictly speaking the same thing has always been sufficient for me not to lose any sleep over it.

Cheers

Richard

"Wolfram Roesler" <wr_at_grp.de> wrote in message news:Xns9272606BF7D48wrgrpde_at_62.153.159.134...
> ctcgag_at_hotmail.com wrote in news:20020821133838.353$Ug_at_newsreader.com:
>
> > I have a great idea, lets make numeric zero also be null. It worked
> > for the Romans.
>
> You perfectly got my point. '' is for strings what 0 is for integers.
> Remember how long it took mankind to accept the fact that it's
> useful to have a symbol for "nothing".
>
> Regards
> W. Roesler
Received on Thu Aug 22 2002 - 03:08:31 CDT